Ultrasound systems are becoming increasingly important tools for non-invasive medical diagnostics. Consequently, ultrasound imaging systems featuring reduced power consumption and improved portability are desirable. Digital signal processors (“DSPs”) have been used to reduce power and increase portability of various types of medical imaging systems, including ultrasound systems.
The most common operating modes of ultrasound systems are Brightness mode (“B-mode”) and Color Doppler Mode. In B-mode, an ultrasound system transmits sound waves of a particular frequency into the body of interest and records the received echoes as a function of time and position to image structural information. The brightness of each point on a display represents the amplitude of the sampled echoes. Color Doppler mode is similar to B-mode but transmits multiple pulses (an ensemble) and uses the relative time (phase) between received echoes to estimate blood flow characteristics. Commonly estimated flow parameters include flow strength (power), direction, velocity, and turbulence.